Drawing instrument.



A. HoLz.

` Patem my is, 1399,

`-mmwlm; INSTRUMENT.

(Applcnt ed Dec. 31, 1897.)

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UNITED "STATES "PATENT FFIC.

ARNO HOLZ, or WILMERSDORF, GERMANY. e

DRAWING` INSTRUMENT.

SPECIFICATION forming part of Letters I Pratent No. 629,028, dated July 18, 1899.

Application iiled December 31,189?. `Serial No. 664,947. (No model.)

To all whom it may concern,.-

tor heretofore necessary in executing geomet- Y rical designs by providing a single instrument which can be adapted to-perform the work of both, and the invention is summarized in the claims, and the accompanying drawings illustrate two useful instruments embodying the invention.

Figure 1 shows a plan view of one form of the device; Fig. 2, a plan view of a modification thereof, Figs. 3 and e illustrating geo! metrical designs drawn by the aid of the instrument shown in Fig. l, and Figs. 5 and 6 are other designs drawn by the aid of the instrument shown in Fig. V2. l

T he invention consists, essentially, in the employment of two or more concentrically-- disposed frames arranged in the same plane and rigidly connected at one or more points, so as to hold them in proper relative position,

and may each be properly scaled for the convenience of the draftsman.

As shown in Fig. 1,the instrument is formed of an inner square frame A and an outer conl centric Vsquare frame A2, and these frames are connected by a stem A, as sbown in Fig. 2. The inner and outer frames B B2 are six-sided and connected by a stem B.

Obviously theparticular geometrical form of the frames may be varied within the scope of the invention, the essential feature being that two or more frames of like form be concentrically arranged in the same plane.V

Having thus described my inventiomwhat I therefore claimas new, and desire to secu re by Letters Patent, is

1. A drafting instrument composed of a ,number of similar concentrically-arranged frames, arranged in the Same plane and rigidly connected.

2. A drafting instrument consisting of in; ner and outer concentrically-arran ged polygonal frame-like pieces lying in the same plane `and rigidly united.

3. A drafting instrument composed of iuner and ou ter polygonal frames of similar contourarranged in the same plane and rigidly united, and each properly scaled, for the purpose and substantially as described.

' ln witness whereof I have hereunto set my hand in presence of two witnesses.

ARNO HOLZ.

Witnesses: l I v CRAs. A H. DAY, KAR -HENSMAN y. 

